Improvement in balanced slide-valves



H. HENDBICKSON.

. Balanced Slide-Vaives.

No. 134,203. I 4 Patented Dec.24, 1872.

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UNITED STATES PATENT QFFICE.

HUBBARD HENDBIGKSON, OF RED BANK, NEW JERSEY.

IMPROVEMENT IN BALANCED SLIDE-VALVES.

Specification forming part of Letters Patent No. 134,203, dated December24, 1872.

To all whom it may concern:

Be it known that I, HUBBARD HENDRICK- SON, of Red Bank, in the county ofMonmouth and State of New Jersey, have invented a new and ImprovedSlide-Valve, of which the following is a specification:

. invention consists, first, in connecting a pivoted yoke with theslide-valve, said yoke having a vertical stem that swings at its upperThis pivot is supported in a tube or cylinder, which is held balanced bythe steam, so that the actual support is applied to the valve by thesteam, but indirectly under said cylinder, and thence to the pivot atthe upper end of the rod. The invention also consists in the arrangementof the various details of the invention, whereby the main idea, aboveset forth, is more fully carried out.

In the accompanying drawing, the letter A represents the slide-valve, ofsuitable size, shape, and kind; It works in the steam-chest B over theports a, b, and c, substantially in the same manner as otherslide-valves. G is a yoke straddling the slide-valve and pivoted theretoat its ends. D is a rod projecting upward from the yoke into a verticalcylinder, E, that is applied above the steam-chest, as shown. The upperend of the rod D is by a pin, 6, pivoted in the upper end of the tube E.As the slide-valve moves back and forward in the steam-chest the rod Dwill swing on its pivot e in conformity with and following the motionsof the slide-valve. The lower end of the tube E enters an opening in thetop of the steam-chest, and has directly above said top f anoutwardly-projecting flange, g. Steam is admitted under this flangethrough holes h in the top of the steam-chest, so that the cylinder Ewill be balancedthat is to say, held on the steam-cushion under itsflange 9, there being thus steam under the tube E, which tends toelevate the same. The valve that is suspended by the pin 0 from saidtube will be raised ofi its seat at least as much as is necessary toavoid friction. The tube E is held and guided in a cylindricalprojection, F, that is built upon the steam-chest, as shown. Suitablepacking-rings i prevent the escape of steam around E within F. Steam is,in a pipe or steam passage j, also carried to above a flange orshoulder, l, of the tube, so that by this means the tube can also bedepressed by steam-power. The proportionate differences in the arealextents of the shoulders g and Z will determine the greater or lesspressure upward applied to the cylinder E, so that thus the balancing ofthe valve can be regulated by enlarging or reducing the respectiveflangesurfaces. on is a pipe projecting from the cylinder F, for thedischarge of steam therein contained. The pipes j and m are providedwith cocks to control the passage of steam through them.

Having thus described my invention ,I claim as new and desire to secureby Letters Patentp 1. The means described for exerting a yield ingpressure upon a slide-valve to hold it firmly to its seat at all partsthereof, but with- 'out unnecessary friction, consisting of the pivotedyoke-rod O D and a steam-balanced cylinder, E, as set forth.

2. The means described for enabling the downward pressure of asteam-balanced cylinder, E g h, to be increased, consisting of theflange l, cavity thereabove, and steam-inlet, all arranged as specified.

HUBBARD HENDRIGKSON.

Witnesses:

A. V. BRIEsEN, T. B. MosHER.

